--- title: "BYD Battery-Box Premium HVM 22.1 vs Dyness Tower T21 - Battery Comparison | ComparePV" description: "Compare BYD Battery-Box Premium HVM 22.1 vs Dyness Tower T21 side by side: shop prices, usable energy, round-trip efficiency, power, cycle life and the full specification." source: "https://comparepv.com/compare-batteries/byd-battery-box-premium-hvm-22-1/dyness-tower-t21" updated: 2026-01-11 --- # BYD Battery-Box Premium HVM 22.1 vs Dyness Tower T21 4 differences, none of them an advantage The largest is usable energy: 0.77 kWh apart. 5 of 9 comparable parameters are identical, with 24 more left out because at least one datasheet does not publish them. ## The two batteries | Attribute | A | B | | --- | --- | --- | | Battery | [BYD Battery-Box Premium HVM 22.1](https://comparepv.com/battery/byd-battery-box-premium-hvm-22-1) | [Dyness Tower T21](https://comparepv.com/battery/dyness-tower-t21) | | Manufacturer | BYD | Dyness | | Usable energy | 22.08 kWh | 21.31 kWh | | Cells and voltage | LFP HV | HV | ## Price offers | Shop | Country | Battery-Box Premium HVM 22.1 | Tower T21 | | --- | --- | --- | --- | | www.solar-outlet.nl | Netherlands | 8 177.95 € | | [See 121 BYD offers](https://comparepv.com/offers?manufacturer=byd&product_type=battery) [See 20 Dyness offers](https://comparepv.com/offers?manufacturer=dyness&product_type=battery) ## Where they differ Ranked by how much the difference matters, not by datasheet order. | Parameter | Battery-Box Premium HVM 22.1 | Tower T21 | Difference | | --- | --- | --- | --- | | Usable energy | 22.08 kWh | 21.31 kWh | 0.77 kWh apart | | Nominal voltage | 410 V | 576 V | 166 V apart | | Ingress protection | IP55 | IP54 | IP55 vs IP54 | | Dimensions | 2160x585x298 mm | 1500x504x380 mm | 2160x585x298 mm vs 1500x504x380 mm | ## Every compared parameter | Parameter | Battery-Box Premium HVM 22.1 | Tower T21 | | --- | --- | --- | | Usable energy | 22.08 kWh | 21.31 kWh | | Nominal energy | - | 21.31 kWh | | Depth of discharge | - | 100 % | | Max system capacity | 66.2 kWh | - | | Modules per stack | - | 2-6 | | Continuous discharge power | - | 12.78 kW | | Continuous charge power | - | 12.78 kW | | Peak discharge power | - | - | | Power per kWh | - | 0.60 kW/kWh | | Round-trip efficiency | 96.0 % | - | | Cycle life | - | 6000 cycles | | Cycle test depth | - | - | | Capacity at end of life | - | - | | Self-discharge | - | - | | Voltage class | High voltage | High voltage | | Nominal voltage | 410 V | 576 V | | Operating voltage | 320-472 V | - | | Cell chemistry | LFP | - | | Active cell balancing | - | - | | Thermal management | - | - | | Inverter | None (battery only) | None (battery only) | | Inverter power | - | - | | Grid connection | - | - | | Backup power | - | - | | Weight | - | 269.0 kg | | Weight per kWh | - | 12.6 kg/kWh | | Dimensions | 2160x585x298 mm | 1500x504x380 mm | | Ingress protection | IP55 | IP54 | | Outdoor-rated | - | - | | Min operating temperature | -10 °C | -10 °C | | Max operating temperature | 50 °C | 50 °C | | Warranty | 10 yrs | 10 yrs | | Warranted throughput | - | - | ## Related comparisons - [BYD Battery-Box Premium HVM 22.1 vs Deye GB-L24](https://comparepv.com/compare-batteries/byd-battery-box-premium-hvm-22-1/gb-l24) - 7 differences, the largest is max system capacity - [BYD Battery-Box Premium HVM 22.1 vs Deye GB-SL-EU (6 modules in series)](https://comparepv.com/compare-batteries/byd-battery-box-premium-hvm-22-1/gb-sl-eu-6-modules-in-series) - 8 differences, the largest is max system capacity - [BYD Battery-Box Premium HVM 22.1 vs Deye GB-L (6 modules in series)](https://comparepv.com/compare-batteries/byd-battery-box-premium-hvm-22-1/ningbo-deye-ess-technology-co-ltd-gb-l-6-modules-in-series) - 7 differences, the largest is max system capacity - [Dyness Tower T21 vs Dyness Tower Pro TP23](https://comparepv.com/compare-batteries/dyness-tower-t21/dyness-tower-pro-tp23) - 14 differences, the largest is usable energy - [Dyness Tower T21 vs Huawei LUNA2000-21-S1](https://comparepv.com/compare-batteries/dyness-tower-t21/huawei-luna2000-21-s1) - 12 differences, the largest is usable energy --- Source: https://comparepv.com/compare-batteries/byd-battery-box-premium-hvm-22-1/dyness-tower-t21 Not in this file, on the page: a written summary generated on request.